Those who enter through the back door can expect to be shown out through the window
It is thrifty to prepare today for the wants of tomorrow.
Betray a friend, and you'll often find you have ruined yourself.
Better one safe way than a hundred on which you cannot reckon.
Appearances are often deceiving.
If you are wise you won't be deceived by the innocent airs of those whom you have once found to be dangerous.